Melee Combat: Combat in Holmes is much the same as all forms of old-school D&D; roll 1d20, look on a chart to see what Armor Class you hit, and roll damage if you landed a blow. All melee damage for weapons is rolled using 1d6, which is a throwback to OD&D. The variable damage by weapon type that was introduced in Supplement I is mentioned briefly as an option in advanced play. Monsters still get their variable damage, though. Sometimes it’s good to be the DM.
The charts used for combat are described by Holmes as ‘extremely complicated’, which is pretty laughable if you’ve ever taken a look at stuff like Rolemaster. The chart is otherwise the same for PCs here as it was in OD&D. The biggest change is for Normal Men. In OD&D they fought as 1st level fighters, but now they are slightly worse than that. The chart for monsters attacking is also much the same as in OD&D, except that the hit dice categories are very slightly tweaked.
Armor class is briefly discussed and expanded upon. Although each number from 9 to 2 is assigned a specific armor type, in general this only applies to humans and humanoids. The various non-human creatures are assigned a number based on the toughness of their hide, their size, and their speed, with armor type not really being a factor. Mechanically it doesn’t mean anything, but it’s the first time AC gets talked about in this way.
Poisoned Weapons: I’m not entirely certain what the rules here mean. Anyone hit by a poison attack must ‘make his saving throw against poison or paralysis and also take the number of damage points indicated by the die roll’. So what happens to a character who fails his save? I assume a failed save vs. poison means death, and the rule about taking damage just refers to the monster’s standard attack damage.
Fire: We gets some new rules for setting oil on fire, as well as the use of flaming oil as a weapon. The siege rules for Chainmail had previously discussed burning enemies with oil, and they were also updated for Swords & Spells. In OD&D, burning oil is briefly mentioned as a way to deter pursuers. But here it’s full-on Molotov cocktail time, with the oil dealing a massive 1d8 on the first round and 2d8 on the second. When you consider that every weapon deals only 1d6, that’s huge. Attacking with oil ignores Armor Class as well, using only Dexterity and size to determine how difficult the target is to hit. Honestly, flaming oil is easily the deadliest option available to characters in the Holmes rulebook.
Wraiths and spectres are immune to burning oil, as are all fire-wielding monsters. Wights and mummies take half damage, and I have to say that the last one surprises me. I’ve played a bunch of D&D inspired games in which mummies are extra-susceptible to fire, so it’s kind of weird to see the opposite in effect here.
Holy Water: This item could be purchased in OD&D, but there were no mechanical benefits described in those rules. Presumably it was up to the referee to house rule it based on general vampire lore. Here holy water is given the same effect on undead that burning oil has on other creatures.
Missile Fire: Ranges are given for the various missile weapons that mostly match up with those in Chainmail. The range of the javelin has been extended from 60 feet to 80 feet, and slings have been given a range whereas previously they had not been dealt with. The same bonuses and penalties still apply to firing at short and long ranges. The ranges are converted to yards when outdoors, as weapons may be fired further (this is straight out of Chainmail). Long range fire (as well as slings) is also pretty much unusable in dungeons, unless the roof is high enough.
Cover: Characters behind cover are harder to hit with missile fire. The rules also expressly forbid characters firing into melee. Way to dodge the question, Holmes!